I moved to stuttgart on saturday (will be stayin here for 6 months). I read the forums here on the tchibo internet stick.

So I went to the store and got the USB stick and SIM for 59.95 Euro. Then yesterday I activated a 20 Euro topup and texted "START DATENFLAT" to 7777 to start the service.

I am in Suttgart West and initially I am getting GPRS but it then switches to UMTS and HSDPA (blue/light blue indicator). All of a sudden it stops working so I have to plug/unplug and it gets back to working. Then I stop getting UMTS and just now I only have GPRS.

My german is bad so when I dial the number I dont understand what they are saying. I know they want me to register

So 3 questions:
Can I register at a tchibo store, will they help me with tihs problem?
What do I need for registration?
Does anyone know why I am only getting GPRS and not even EDGE at the moment? I am in an coverage area.

Hi Fredo,
usually the card should have been registered when you purchase it in the store. Didnt you fill out such a form there where you have to enter your adress and other personal information? If no i would try to get it done in the store. "Ich muss meine SIM-Karte registrieren lassen". You can show them the SMS - if they are kind maybe they call there for you.

Regarding GPRS/UMTS - maybe you are at a place where UMTS is quite low. So if UMTS fieldstrength is too low it does fallback to GPRS. EDGE is only available in a few places, not everywhere troughout the country.

Another possiblity is that the stick takes too much power from your USB port. We have the problem with the USB modems that we manufacture. We recommend customers to get a Y-USB cable that takes power from 2 USB ports. This usually increases the performance as well.

As you figured out correctly Tchibo wants you to register your SIM. Usually that should have happend already upon purchase at your local Tchibo shop. But sometimes the shop employees forget to fax the registration form or it arrives illegible.
Now you can either register by phone or fill out this form once more and drop it at a Tchibo shop or send it directly by fax to the number given on the form.

Regarding coverage, O2 doesn't have nationwide EDGE-coverage yet. They started EDGE-rollout last year, but their priority was rural areas where there's no 3G-coverage available. So especially in the bigger cities like Stuttgart there are still some GPRS-only cells, as there should be sufficient 3G-coverage.
The fact you are being served by a 2G-cell doesn't necessarily mean, that there's no 3G-coverage. Network operators define levels, when terminals should switch from one cell to another and they can also force terminals to switch to 2G-cells if a 3G-cell is congested (so called "overload protection"). You could try forcing your USB modem to use 3G only allthough reception could be low or the cell congested and so to ignore commands from the network. Therefore open Mobile Partner, go to Einstellungen/Tools | Optionen/Options | Netzwerk/Network and chose only 3G/UMTS/WCDMA as Netwerktyp/Network Type. Now check if you get reception, especially if it improves near windows. If so buy an USB-extension cable (I do recommend on with a foot like this for € 6 incl. shipping) and place the USB modem on a window sill.
If you have bad luck and don't get any signal in 3G-only mode, switch Mobile Partner back to automatic network type selection.
Also note that on 3G networks there's an effect called cell breathing, which means that the coverage footprint of 3G cells varies dependant on the number of terminals and data throughput. So theoretically you could have 3G-coverage during the night, but not during the day.

It took a few tries but I was able to register through their website.
The UMTS works better in one corner of my small studio (away from the window) but even then sometimes it will switch to the light blue and green.

Sometimes during the day it wont work and I only get GPRS but other hours it will give me 3g (especially at night). Really spotty coverage, like what you mentioned inquisitor.

Sometimes this happens
-Light will stay blue, but no data transmisison. Mobile Partner shows UMTS in the lower left.
-So I take out the stick and plug it back in, then it is just a flashing green light but I get no signal in mobile partner.
-Restarting the computer sometimes gets me (sometimes) a 3g signal (blue light) again

Could it also be a driver issue? I am running the Windows 7 release candiate.
Also, is the USB stick supposed to get really hot? It heats up quick!

I dont know how relevant i am. But can it be a sim issue? A faulty sim card? One of my sim got some issue with 3G from home. I got to try 5 to 7 times so it access 3G and i am left with gprs or normal 2.5G reception most of the time. In my university i can easily log into 3G networks with same sim.

I Crosse checked the issue with few other sims and those never had such problems and worked perfect from home. In my case its an Etisalat sim not a tchibo sim.

Thats only a sign that you are in an area without good coverage. If they have to send with full power the casing of these sticks is mostly too small and has no ventilation holes at all. So the modem itself can get very hot.

I got a Tchibo data stick (E160) last year in Germany and will use it again. But I'd like to use it also in Italy. Does it come unlocked? Can I get an Italian data sim and use it in the same device? What about a Croatian sim?

The Tchibo stick is netlocked, so it can be used only with German O2 SIM cards. But unlocking has become very easy: Just calculate your individual unlock code at Online Huawei Modem Unlock Calculator, insert a SIM card from any other operator in your stick and start Mobile Partner. After requesting the PIN code for the SIM card, Mobile Partner will ask you to enter the unlock code, which will unlock your modem permanently.
Afterwards you'll just need to create a connection profile for your new provider as described at Huawei Mobile Partner - 3G modem wiki.

And yes, you can use any Italian or Croatian SIM in your Tchibo stick, as it fully supports all Italian an Croation networks. I think there are threads about prepaid data offers for both countries somewhere on this board.